Safety switch



Dec. 27, 1932.

S. W. MAUGER SAFETY SWITCH Filed Sept. 4, 1950 IrK/entor: Salm mel W.Maugeri H iS Attorreg.

LPatented Dec. 27,A 1932 SAMUEL w. MAUGER,

SAFETY Application filed September The present invention relates ytosafety switches and more particularly to switches wherein the electricalcircuit between switch contacts varc may be drawn or where a circuit toground may be completedk through the operator. Furthermore, there isalways a danger of fuses blowing inthe operators face, which may resultin severe burns to the face and hands or injury to the eyes..

The object of the invention is the provision of a fused safety switch'which is simple in structure, low in costand which provides maximumprotection to the` operator when opening or closing the switch or whenre-k moving or replacing the fuses.

The. invention will be more. clearly understood iit reference is hadtothe accompanying drawing, of which F ig. 1' is avertical sectionparallel to thel fuses; Fig. 2 is a similar section .at right angles tothat of F ig. 1 of a fused switch embodyingthe invention; Fig. 3 is aviewo'f the operating handle partly in section an d showingr the meansfor locking it in place on the switch operating rods, and Fig. 4t is aninner end view of the handle portion shown in Fig. 3.

In order that maximum protection may he` provided to the operator, theswitch mechanism 5 is mounted on the rear side of an in sulatingswitchboard 6 in such a manner that it may he operated only by a personstanding in front of the switch board and manually pulling out 'orpushingk in on the handle 7, depending on whether the switch is to heopened orclosed. A The door panel 9 of the switch hoard, mount-ed justin front of the switch 5 is pivotally7 held in placeas by the springhinges 11. These hinges are under suliicient tension to maintain thepanel in closed position unless it is held or blocked open'. As a.positive assurance against opening this panel when the switch is inclosed position, the switch handle 7 is interlocked with the panel insuch of the handle.-

SWITCH l 4, 1930. serial No. 9,730.

a manner that it must lirst he removed, which can only be done when theswitch 5 is in open position. y j Interlocking of the handle 7 with thepanel 9 is accomplished hy providing the handle with inwardlyyprojecting ends 8,. which when the switch 5 is closed, extend into andthrough apertures 10 cut from the panel 9.

The ends of the handle are recessed to form sockets therein, adapt-ingthe handle tohe 3 and el) pivotally held by pin 20 inthe'longitudinalslots 16 cut or formed in the ends The latch isprovided, interorsoHiiNncTAnY, NEWVYORK, Assrenoit To GENERAL ELECTRIC fGoMrANrA CORPORATION or NEW YORK media-te its ends, with downward'projecting V-shaped catches orlugs 17 adapted to seat in similar shapedrecesses in the ends of:

switch operating rods v13; y

The inner end of the latch is provided with a circular spring clip 19which yieldingly slips down over rod 13 when the latch 1'5 is pusheddown into locking position', and holds it releasably inl place.` vAs theback or top of the latch v15 falls flush with the upper side' of thehandle 7. kThe latchf15 is also provided withan inwardlextension orthumb rpiece 21 which the operator grips when he intends to liftit inorder to release the handle 7 from the` ends of rods 13. But as will hehereinafter explained', releasing of the handle from the switch rods isonly possible when the switch'is inopen position.

The inner ends of the switch operating' `rods are threaded and extendthrough a slidable insulating base'22, where they are securely locked inplace by suitable nuts. .Thisn alonof four `sta or O'uiderods 24 whichare threaded at each end, the left ends being se eurely clamped to theswitch board 6 and angle irons 47 by nuts 25 while the rlghtends serveto hold yand clamp the iXed insulating base or panel`26 to the angleviron supports 27, or in a position directly in back of slidable base22.

The tixed base 26 acts as a support for three pairs of blades 28, eachpair being held in vertical alignment by annular shoulders 29 and nuts31 screwed on the rear end of the threaded extensions or studs 30 whichpass through apertures in the base. Nuts 31 may be used also to clampterminal lugs of circuit wires in electrical contact with the rear endsof the blade studs.

Mounted in the slidable base 22 in suchy a position as to align up withthe blades 28 are three pairs of switch jaws 32, formed from suitablestrips of spring metal bent to the shape shown and inserted in slotsthrough the base. Sections of angle iron 33 are welded or suitablyfastened to the sides of the strips and act to clamp the jaws in placeso that when the slidable base 22 is pushed inward the jaws 32 willyieldingly slip over the blades 28 and make good electrical contacttherewith.

Each set of jaws are joined electrically through cartridge fuses 34releasably held in place and connected electrically to the jaws byspring clips 35 which are attached to the forward extension 32a of jawforming strips 32.

The lock nuts on the switch operating rods 13 are so adjusted that whenthe switch jaws 32 are over the ends of blades 28 or when the switch isin closed position, the inwardly projecting ends of the handle 7 willproject inward through the apertures 10 in the swinging panel 9 thuspreventing the lifting ofthe latch 15 and the detachment of the handle 7from the ends of the switch operating rods 13. It will be noticed thatas long as the handle is held in place on the switch operating rods 13the panel 9 cannot be opened, thus preventing access to the switch orfuses.

On the other hand when the switch 5 is in open position the inwardlyprojecting ends of the handle will be free of the switch board or infront of it and the latch members 15 may be lifted, the handle removedfrom the switch operating rods 13 and the panel 9 swung open, permittingaccess to the inside of the enclosure in order that the fuses 34 may beremoved or replaced.

It will be further observed that when the switch is in open position andthe panel 9 swung open, the sliding base 22 acts as a barrier betweenthe operator and the charged blades 28 or if the switch is in closedposition the panel 9 acts as a barrier between the fuses and theoperator, he being thus always protected from live parts by one or theother of the barriers.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is:

1. A fused switch having in combination, a switch board, provided with aswinging panel, a fixed base board disposed rearwardly of said swingingpanel, a movable base disposed intermediate said xed base and swingingpanel, means for guiding the said movab e base, a plurality of contactsmounted in said movable base and adjacent to said fixed base, removableelectrical fuses mounted on the side of said movable base adjacent tosaid swinging panel and connecting said contacts by pairs, contactsmounted in said fixed base in alignment with said movable contacts,means extending through said swin ing panel for reciprocating saidmovable ase, and means for interlocking said swinging panel therewithwhereby it may be swung open only when said switch is in open position.

2. A reciprocating switch, a handle for 0perating sai switch, a movablepanel dis osed intermediate said switch and said han le, a rod connectedto the movable part of said switch and (projecting through said paneland having sai handle mounted on the end of said rod, and a lockingmeans releasably securing said handle to said rod, said means capable ofbeing unlocked only when said switch is in open position.

3. A safety switch comprising an enclosure provided with a movablepanel, stationary contacts mounted in said enclosure opposite saidpanel, a transverse barrier plate movable between said stationarycontacts and said panel and provided on the front side with fuse clipsand on the rear with switch contacts electrically connected respectivelyto said fuse clips, rods connected to said barrier and extending towardsaid panel, and an operating handle for said barrier extending throughsaid panel and locked to said rods while the switch is in closed circuitposition and capable of being detached therefrom while in withdrawn opencircuitposition and permitting the panel to be opened.

In witness whereof I have hereunto set my hand this 3rd da of September,1930.

S MUEL W. MAUGER.

